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Streffer JR, Papassotiropoulos A, Kurosinski P, Signorell A, Wollmer MA, Tsolaki M, Iakovidou V, Hörndli F, Bosset J, Götz J, Nitsch RM, Hock C. Saitohin gene is not associated with Alzheimer's disease. J Neurol Neurosurg Psychiatry 2003; 74:362-3. [PMID: 12588928 PMCID: PMC1738341 DOI: 10.1136/jnnp.74.3.362] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND The deposition of tau protein in neurofibrillary tangles constitutes an important feature of many neurodegenerative disorders, including Alzheimer's disease. A polymorphic gene, saitohin (STH), nested within the tau gene (microtubule associated protein tau, MAPT), was recently identified and an association of a non-synonymous polymorphism in STH with increased risk for Alzheimer's disease was suggested. OBJECTIVE AND METHODS To test the above hypothesis in a case-control association study of two independent white populations within Switzerland and Greece, comparing genotype and allele frequencies from 225 Alzheimer's disease patients and 144 healthy control subjects. RESULTS No differences in allelic or genotypic distributions between Alzheimer's disease patients and controls was found in the individual samples (Swiss/Greek) or in the combined sample. Stratification for the presence of apolipoprotein E (APOE) epsilon 4 allele, sex, or age did not show significant effects in the populations studied, nor was there an effect on the age of onset. CONCLUSIONS No evidence was found for an association of the non-synonymous polymorphism (Q7R) in STH and Alzheimer's disease. This finding is in line with earlier studies showing no association between MAPT and Alzheimer's disease.
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Götz J, Zick K. Local Velocity and Concentration of the Single Components in Water/Oil Mixtures Monitored by Means of MRI Flow Experiments in Steady Tube Flow. Chem Eng Technol 2003. [DOI: 10.1002/ceat.200390008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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53
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Götz J, Lankes H, Weisser H, Sommer K. Characterization of Products Consisting of Synthetic, Amorphous Silica and Water with Different Moistures by Means of NMR. Chem Eng Technol 2002. [DOI: 10.1002/1521-4125(20021008)25:10<989::aid-ceat989>3.0.co;2-k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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54
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Götz J, Carlsson J, Schipmann R, Rohde M, Sorges E, Manz F, Tebbe U. [37-year-old patient with eye muscle paralysis and rapidly progressing respiratory insufficiency]. Internist (Berl) 2002; 43:548-53. [PMID: 12053411 DOI: 10.1007/s00108-001-0449-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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55
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Götz J, Tolnay M, Barmettler R, Ferrari A, Bürki K, Goedert M, Probst A, Nitsch RM. Human tau transgenic mice. Towards an animal model for neuro- and glialfibrillary lesion formation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2001; 487:71-83. [PMID: 11403167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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56
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Götz J, Chen F, van Dorpe J, Nitsch RM. Formation of neurofibrillary tangles in P301l tau transgenic mice induced by Abeta 42 fibrils. Science 2001; 293:1491-5. [PMID: 11520988 DOI: 10.1126/science.1062097] [Citation(s) in RCA: 1074] [Impact Index Per Article: 46.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
beta-Amyloid plaques and neurofibrillary tangles (NFTs) are the defining neuropathological hallmarks of Alzheimer's disease, but their pathophysiological relation is unclear. Injection of beta-amyloid Abeta42 fibrils into the brains of P301L mutant tau transgenic mice caused fivefold increases in the numbers of NFTs in cell bodies within the amygdala from where neurons project to the injection sites. Gallyas silver impregnation identified NFTs that contained tau phosphorylated at serine 212/threonine 214 and serine 422. NFTs were composed of twisted filaments and occurred in 6-month-old mice as early as 18 days after Abeta42 injections. Our data support the hypothesis that Abeta42 fibrils can accelerate NFT formation in vivo.
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Götz J, Nitsch RM. Compartmentalized tau hyperphosphorylation and increased levels of kinases in transgenic mice. Neuroreport 2001; 12:2007-16. [PMID: 11435938 DOI: 10.1097/00001756-200107030-00045] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The formation of neurofibrillary tangles in Alzheimer's disease is preceded by a pretangle stage of hyperphosphorylated tau. To characterize pretangle tau in vivo, we correlated, in human tau transgenic mice, levels of kinases known to phosphorylate tau in vitro with the phosphorylation of tau at specific epitopes. Levels of cyclin-dependent kinase-5 were increased in axons of CA1 pyramidal neurons, where tau was phosphorylated specifically at the AD2 epitope Ser396/Ser404. The 12E8 epitope serine262/serine356 and the AT180 epitope threonine231/serine235 were phosphorylated in dendrites, and colocalized with increased levels of glycogen synthase kinase-3. CA1 neurons phosphorylated tau at more epitopes than dentate gyrus neurons, suggesting that tau phosphorylation is cell type-specific, a possible explanation for the spatial distribution of neurofibrillary tangles.
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Abstract
Advances in genetics and transgenic approaches have a continuous impact on our understanding of Alzheimer's disease (AD) and related disorders, especially as aspects of the histopathology and neurodegeneration can be reproduced in animal models. AD is characterized by extracellular Abeta peptide-containing plaques and neurofibrillary aggregates of hyperphosphorylated isoforms of microtubule-associated protein tau. A causal link between Abeta production, neurodegeneration and dementia has been established with the identification of familial forms of AD which are linked to mutations in the amyloid precursor protein APP, from which the Abeta peptide is derived by proteolysis. No mutations have been identified in the tau gene in AD until today. Tau filament formation, in the absence of Abeta production, is also a feature of several additional neurodegenerative diseases including progressive supranuclear palsy, corticobasal degeneration, Pick's disease, and frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17). The identification of mutations in the tau gene which are linked to FTDP-17 established that dysfunction of tau can, as well as Abeta formation, lead to neurodegeneration and dementia. In this review, newly recognized cellular functions of tau, and the neuropathology and clinical syndrome of FTDP-17 will be presented, as well as recent advances that have been achieved in studies of transgenic mice expressing tau and AD-related kinases and phosphatases. These models link neurofibrillary lesion formation to neuronal loss, provide an in vivo model in which therapies can be assessed, and may contribute to determine the relationship between Abeta production and tau pathology.
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Götz J, Tolnay M, Barmettler R, Chen F, Probst A, Nitsch RM. Oligodendroglial tau filament formation in transgenic mice expressing G272V tau. Eur J Neurosci 2001; 13:2131-40. [PMID: 11422454 DOI: 10.1046/j.0953-816x.2001.01604.x] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Genetic evidence indicates that several mutations in tau, including G272V, are linked to frontotemporal dementia with parkinsonism. We expressed this mutation in mouse brains by combining a prion protein promoter-driven expression system with an autoregulatory transactivator loop that resulted in high expression of human G272V tau in neurons and in oligodendrocytes. We show that G272V tau can form filaments in murine oligodendrocytes. Electron microscopy established that the filaments were either straight or had a twisted structure; these were 17-20 nm wide and had a periodicity of approximately 75 nm. Filament formation was associated with tau phosphorylation at distinct sites, including the AT8 epitope 202/205 in vivo. Immunogold electron microscopy of sarcosyl-extracted spinal cords from G272V transgenic mice using phosphorylation-dependent antibodies AT8 or AT100 identified several sparsely gold-labelled 6-nm filaments. In the spinal cord, fibrillary inclusions were also identified by thioflavin-S fluorescent microscopy in oligodendrocytes and motor neurons. These results establish that expression of the G272V mutation in mice causes oligodendroglial fibrillary lesions that are similar to those seen in human tauopathies.
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Götz J, Barmettler R, Ferrari A, Goedert M, Probst A, Nitsch RM. In vivo analysis of wild-type and FTDP-17 tau transgenic mice. Ann N Y Acad Sci 2001; 920:126-33. [PMID: 11193141 DOI: 10.1111/j.1749-6632.2000.tb06914.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Mutations in the coding and intronic regions of the tau gene cause frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17). Some of these mutations lead to an overproduction of tau isoforms with four microtubule-binding repeats, followed by the development of fibrillary lesions and selective cell death. In order to analyze the development of these neurofibrillary lesions in transgenic mice, the longest four-repeat human brain tau isoform was expressed under control of two different neuron-specific promoters. In a first model, utilizing the human Thy1 promoter, transgenic tau was hyperphosphorylated and abnormally localized to cell bodies and dendrites. In a second model, which made use of a human Thy1.2 expression vector, transgenic expression levels were much higher, and an additional phenotype was observed: Large numbers of pathologically enlarged axons containing neurofilament- and tau-immunoreactive spheroids were present, especially in spinal cord. Signs of Wallerian degeneration and neurogenic muscle atrophy were observed. Behaviorally, transgenic mice showed signs of muscle weakness. Our data show that overexpression of human four-repeat tau in itself is sufficient to lead to nerve cell dysfunction and amyotrophy. We have now extended our initial studies by introducing exonic mutations including G2t 2V and PS01L into the tau gene in order to achieve a more advanced FTDP-17 associated phenotype.
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Götz J, Chen F, Barmettler R, Nitsch RM. Tau filament formation in transgenic mice expressing P301L tau. J Biol Chem 2001; 276:529-34. [PMID: 11013246 DOI: 10.1074/jbc.m006531200] [Citation(s) in RCA: 341] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Mutations in the microtubule-associated protein tau, including P301L, are genetically coupled to hereditary frontotemporal dementia with parkinsonism linked to chromosome 17. To determine whether P301L is associated with fibril formation in mice, we expressed the longest human tau isoform, human tau40, with this mutation in transgenic mice by using the neuron-specific mouse Thy1.2 promoter. We obtained mice with high expression of human P301L tau in cortical and hippocampal neurons. Accumulated tau was hyperphosphorylated and translocated from axonal to somatodendritic compartments and was accompanied by astrocytosis and neuronal apoptosis indicated by terminal deoxynucleotidyl transferase-mediated biotinylated dUTP nick end-labeling staining. Moreover, P301L tau formed abnormal filaments. Electron microscopy of sarcosyl-insoluble protein extracts established that the filaments had a straight or twisted structure of variable length and were approximately 15 nm wide. Immunoelcecton microscopy showed that the tau filaments were phosphorylated at the TG3, AT100, AT8, and AD199 epitopes in vivo. In cortex, brain stem, and spinal cord, neurofibrillary tangles were also identified by thioflavin-S fluorescent microscopy and Gallyas silver stains. Together, our results show that expression of the P301L mutation in mice causes neuronal lesions that are similar to those seen in human tauopathies.
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Ferrari A, Ehler E, Nitsch RM, Götz J. Immature human NT2 cells grafted into mouse brain differentiate into neuronal and glial cell types. FEBS Lett 2000; 486:121-5. [PMID: 11113451 DOI: 10.1016/s0014-5793(00)02251-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
NT2 cells are a transfectable human embryonal carcinoma cell line, that can be differentiated into postmitotic neuron-like cells (NT2N cells), and transplanted into rodent brains. Differentiation requires a 5-week-long treatment with retinoic acid prior to transplantation. Here, we show that this step can be omitted, and that undifferentiated NT2 cells migrate over long distances and differentiate into both neuron- and oligodendrocyte-like cell types upon grafting into brains of immunocompetent newborn mice. Grafted cells can be traced by fluorogold, with no evidence for tumor formation. Our approach provides an experimental model system which allows the immunohistological and biochemical study of neuronal and glial differentiation of human cells in vivo, and which may be suitable as an in vivo model for pharmacological studies.
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63
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Götz J, Schneider J, Weisser H. Korrelation zwischen der dynamischen Viskosität und der T2-Relaxationszeit aus NMR-Messungen für reine Flüssigkeiten, Lösungen und Suspensionen. CHEM-ING-TECH 2000. [DOI: 10.1002/1522-2640(200009)72:9<1074::aid-cite10742>3.0.co;2-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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64
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Götz J, Probst A, Mistl C, Nitsch RM, Ehler E. Distinct role of protein phosphatase 2A subunit Calpha in the regulation of E-cadherin and beta-catenin during development. Mech Dev 2000; 93:83-93. [PMID: 10781942 DOI: 10.1016/s0925-4773(00)00267-7] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Protein phosphatase 2A (PP2A) plays central roles in development, cell growth and transformation. Inactivation of the gene encoding the PP2A catalytic subunit Calpha by gene targeting generates a lethal embryonic phenotype. No mesoderm is formed in Calpha(-/-) embryos. Here, we found that during normal early embryonic development Calpha was predominantly present at the plasma membrane whereas the highly homologous isoform Cbeta was localized to the cytoplasm and nuclei, suggesting the inability of Cbeta to compensate for vital functions of Calpha in Calpha(-/-) embryos. In addition, PP2A was found in a complex containing the PP2A substrates E-cadherin and beta-catenin. In Calpha(-/-) embryos, E-cadherin and beta-catenin were redistributed from the plasma membrane to the cytosol. Cytosolic concentrations of beta-catenin were low. Our results suggest that Calpha is required for stabilization of E-cadherin/beta-catenin complexes at the plasma membrane.
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65
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Probst A, Götz J, Wiederhold KH, Tolnay M, Mistl C, Jaton AL, Hong M, Ishihara T, Lee VM, Trojanowski JQ, Jakes R, Crowther RA, Spillantini MG, Bürki K, Goedert M. Axonopathy and amyotrophy in mice transgenic for human four-repeat tau protein. Acta Neuropathol 2000; 99:469-81. [PMID: 10805089 DOI: 10.1007/s004010051148] [Citation(s) in RCA: 289] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Coding region and intronic mutations in the tau gene cause frontotemporal dementia and parkinsonism linked to chromosome 17. Some of these mutations lead to an overproduction of tau isoforms with four microtubule-binding repeats. Here we have expressed the longest four-repeat human brain tau isoform in transgenic mice under the control of the murine Thy1 promoter. Transgenic mice aged 3 weeks to 25 months overexpressed human tau protein in nerve cells of brain and spinal cord. Numerous abnormal, tau-immunoreactive nerve cell bodies and dendrites were seen. In addition, large numbers of pathologically enlarged axons containing neurofilament- and tau-immunoreactive spheroids were present, especially in spinal cord. Signs of Wallerian degeneration and neurogenic muscle atrophy were observed. When motor function was tested, transgenic mice showed signs of muscle weakness. Taken together, these findings demonstrate that overexpression of human four-repeat tau leads to a central and peripheral axonopathy that results in nerve cell dysfunction and amyotrophy.
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66
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Götz J, Kues W. The role of protein phosphatase 2A catalytic subunit Calpha in embryogenesis: evidence from sequence analysis and localization studies. Biol Chem 1999; 380:1117-20. [PMID: 10543450 DOI: 10.1515/bc.1999.139] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Protein phosphatase 2A (PP2A) constitutes one of the major families of protein serine/threonine phosphatases found in all eukaryotic cells. PP2A holoenzymes are composed of a catalytic subunit complexed with a structural regulatory subunit of 65 kDa. These core subunits associate with regulatory subunits of various sizes to form different heterotrimers which have been purified and evaluated with regard to substrate specificity. In fully differentiated tissues PP2A expression levels are highest in the brain, however, relatively little is known about expression in the developing embryo. In order to determine the composition of PP2A catalytic subunits in the mouse, cDNAs were cloned and the genomic organization of PP2A Calpha was determined. By a gene targeting approach in the mouse, we have previously shown that the absence of the major catalytic subunit of PP2A, Calpha, resulted in embryonic lethality around embryonic day E6.5. No mesoderm was formed which implied that PP2A plays a crucial role in gastrulation. Here, we extended our studies and analyzed wildtype embryos for Calpha expression at subsequent stages of development. After gastrulation is completed, we find high expression of Calpha restricted to the neural folds, which suggests that PP2A plays an additional pivotal role in neurulation.
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67
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Götz J, Probst A, Ehler E, Hemmings B, Kues W. Delayed embryonic lethality in mice lacking protein phosphatase 2A catalytic subunit Calpha. Proc Natl Acad Sci U S A 1998; 95:12370-5. [PMID: 9770493 PMCID: PMC22838 DOI: 10.1073/pnas.95.21.12370] [Citation(s) in RCA: 173] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Protein phosphatase 2A (PP2A) is a multimeric enzyme, containing a catalytic subunit complexed with two regulatory subunits. The catalytic subunit PP2A C is encoded by two distinct and unlinked genes, termed Calpha and Cbeta. The specific function of these two catalytic subunits is unknown. To address the possible redundancy between PP2A and related phosphatases as well as between Calpha and Cbeta, the Calpha subunit gene was deleted by homologous recombination. Homozygous null mutant mice are embryonically lethal, demonstrating that the Calpha subunit gene is an essential gene. As PP2A exerts a range of cellular functions including cell cycle regulation and cell fate determination, we were surprised to find that these embryos develop normally until postimplantation, around embryonic day 5.5/6.0. While no Calpha protein is expressed, we find comparable expression levels of PP2A C at a time when the embryo is degenerating. Despite a 97% amino acid identity, Cbeta cannot completely compensate for the absence of Calpha. Degenerated embryos can be recovered even at embryonic day 13.5, indicating that although embryonic tissue is still capable of proliferating, normal differentiation is significantly impaired. While the primary germ layers ectoderm and endoderm are formed, mesoderm is not formed in degenerating embryos.
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Shmerling D, Hegyi I, Fischer M, Blättler T, Brandner S, Götz J, Rülicke T, Flechsig E, Cozzio A, von Mering C, Hangartner C, Aguzzi A, Weissmann C. Expression of amino-terminally truncated PrP in the mouse leading to ataxia and specific cerebellar lesions. Cell 1998; 93:203-14. [PMID: 9568713 DOI: 10.1016/s0092-8674(00)81572-x] [Citation(s) in RCA: 393] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The physiological role of prion protein (PrP) remains unknown. Mice devoid of PrP develop normally but are resistant to scrapie; introduction of a PrP transgene restores susceptibility to the disease. To identify the regions of PrP necessary for this activity, we prepared PrP knockout mice expressing PrPs with amino-proximal deletions. Surprisingly, PrP lacking residues 32-121 or 32-134, but not with shorter deletions, caused severe ataxia and neuronal death limited to the granular layer of the cerebellum as early as 1-3 months after birth. The defect was completely abolished by introducing one copy of a wild-type PrP gene. We speculate that these truncated PrPs may be nonfunctional and compete with some other molecule with a PrP-like function for a common ligand.
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69
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Li ZW, Stark G, Götz J, Rülicke T, Gschwind M, Huber G, Müller U, Weissmann C. Generation of mice with a 200-kb amyloid precursor protein gene deletion by Cre recombinase-mediated site-specific recombination in embryonic stem cells. Proc Natl Acad Sci U S A 1996; 93:6158-62. [PMID: 8650236 PMCID: PMC39206 DOI: 10.1073/pnas.93.12.6158] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Gene disruptions and deletions of up to 20kb have been generated by homologous recombination with appropriate targeting vectors in murine embryonic stem (ES) cells. Because we could not obtain a deletion of about 200 kb in the mouse amyloid precursor protein gene by the classical technique, we employed strategies involving the insertion of loxP sites upstream and downstream of the region to be deleted by homologous recombination and elicited excision of the loxP-flanked region by introduction of a Cre expression vector into the ES cells. In the first approach, the loxP sequences were inserted in two successive steps and after each step, ES cell clones were isolated and characterized. Deletion of the loxP-flanked sequence was accomplished by introducing the cre gene in a third step. In the second approach, ES cells containing the upstream loxP cassette were electroporated simultaneously with the downstream loxP targeting vector and the Cre expression plasmid. ES cells were obtained that gave rise to chimeric mice capable of germ-line transmission of the deleted amyloid precursor protein allele.
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70
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Goedert M, Spillantini MG, Jakes R, Crowther RA, Vanmechelen E, Probst A, Götz J, Bürki K, Cohen P. Molecular dissection of the paired helical filament. Neurobiol Aging 1995; 16:325-34. [PMID: 7566342 DOI: 10.1016/0197-4580(95)00017-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Abundant neurofibrillary tangles, neuropil threads and plaque neurites constitute the neurofibrillary pathology of Alzheimer's disease. They form in the nerve cells that undergo degeneration in the disease where their regional distribution correlates with the degree of dementia. Each lesion contains the paired helical filament (PHF) as its major fibrous component. Recent work has shown that PHFs are composed of the microtubule-associated protein tau in a hyperphosphorylated state. PHF-tau is hyperphosphorylated on six adult brain tau isoforms. As a consequence, tau is unable to bind to microtubules and is believed to self-assemble into the PHF. Current evidence suggests that protein kinases or protein phosphatases with a specificity for serine/threonine-proline residues play an important role in the hyperphosphorylation of tau. Candidate protein kinases include mitogen-activated protein kinase, glycogen synthase kinase-3 and cyclin-dependent kinase 5, whereas the trimeric form of protein phosphatase 2A is a candidate phosphatase.
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71
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Götz J, Probst A, Spillantini MG, Schäfer T, Jakes R, Bürki K, Goedert M. Somatodendritic localization and hyperphosphorylation of tau protein in transgenic mice expressing the longest human brain tau isoform. EMBO J 1995; 14:1304-13. [PMID: 7729409 PMCID: PMC398215 DOI: 10.1002/j.1460-2075.1995.tb07116.x] [Citation(s) in RCA: 285] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Microtubule-associated protein tau is the major constituent of the paired helical filament, the main fibrous component of the neurofibrillary lesions of Alzheimer's disease. Tau is an axonal phosphoprotein in normal adult brain. In Alzheimer's disease brain tau is hyperphosphorylated and is found not only in axons, but also in cell bodies and dendrites of affected nerve cells. We report the production and analysis of transgenic mice that express the longest human brain tau isoform under the control of the human Thy-1 promoter. As in Alzheimer's disease, transgenic human tau protein was present in nerve cell bodies, axons and dendrites; moreover, it was phosphorylated at sites that are hyperphosphorylated in paired helical filaments. We conclude that transgenic human tau protein showed pre-tangle changes similar to those that precede the full neurofibrillary pathology in Alzheimer's disease.
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72
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Goedert M, Jakes R, Spillantini MG, Crowther RA, Cohen P, Vanmechelen E, Probst A, Götz J, Bürki K. Tau protein in Alzheimer's disease. Biochem Soc Trans 1995; 23:80-5. [PMID: 7758799 DOI: 10.1042/bst0230080] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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73
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Hébert JM, Rosenquist T, Götz J, Martin GR. FGF5 as a regulator of the hair growth cycle: evidence from targeted and spontaneous mutations. Cell 1994; 78:1017-25. [PMID: 7923352 DOI: 10.1016/0092-8674(94)90276-3] [Citation(s) in RCA: 425] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Fibroblast growth factor 5 (FGF5) is a secreted signaling protein. Mice homozygous for a predicted null allele of the Fgf5 gene, fgf5neo, produced by gene targeting in embryonic stem cells, have abnormally long hair. This phenotype appears identical to that of mice homozygous for the spontaneous mutation angora (go). The fgf5neo and go mutations fail to complement one another, and exon 1 of Fgf5 is deleted in DNA from go homozygotes, demonstrating that go is a mutant allele of Fgf5. Expression of Fgf5 is detected in hair follicles from wild-type mice and is localized to the outer root sheath during the anagen VI phase of the hair growth cycle. These findings provide evidence that FGF5 functions as an inhibitor of hair elongation, thus identifying a molecule whose normal function is apparently to regulate one step in the progression of the follicle through the hair growth cycle.
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74
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Götz J, Sauter R, Steinijans VW, Jonkman JH. Steady-state pharmacokinetics of a once-daily theophylline formulation (Euphylong) when given twice daily. Int J Clin Pharmacol Ther 1994; 32:168-73. [PMID: 8032575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
In a multiple-dose crossover study in 18 healthy male volunteers the steady-state pharmacokinetics of Euphylong, which has been designed for once-daily evening administration, was investigated after conventional twice-daily administration. Under both modes of administration 2 plasma level profiles over 24-hours each were taken during steady-state (day 5/6 and day 8/9, respectively), in order to assess the reproducibility from day to day. The extent of absorption (AUC) was equivalent for both dosing schemes. The intentional differences in pharmacokinetic profiles between the once-daily and twice-daily administration were reflected in the maximum concentrations (15.0 vs 12.1 mg/l), the plateau time T75% Cmax (11.5 vs 17.1 hours), the percent peak-trough fluctuation (94 vs 47%) and the nocturnal excess (37 vs 4%). Results are given for day 8/9, but were practically identical on day 5/6. Thus, the twice-daily administration provides very smooth plasma levels over 24 hours, however, at the expense of the loss of the nocturnal excess which is of clinical relevance in the treatment of nocturnal asthma.
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75
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Vortkamp A, Thias U, Gessler M, Rosenkranz W, Kroisel PM, Tommerup N, Krüger G, Götz J, Pelz L, Grzeschik KH. A somatic cell hybrid panel and DNA probes for physical mapping of human chromosome 7p. Genomics 1991; 11:737-43. [PMID: 1663489 DOI: 10.1016/0888-7543(91)90082-p] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
To identify by reverse genetics genes on the short arm of human chromosome 7 expected to be involved in the regulation of human craniofacial and limb development, we have set up a human mouse somatic cell hybrid panel that divides 7p into 9 fragments. The breakpoints are defined by deletions or translocations involving one chromosome 7 in the cells of the human cell fusion partners. Particularly densely covered with these cytogenetic anchor points is the proximal area of 7p within and around 7p13. The number of cytogenetic mapping points within proximal 7p could be increased by four, using two diploid human cell lines with small interstitial deletions in this region for dosage studies. We used Southern blots of this panel to assign to 7q or subregions of 7p more than 300 arbitrary DNA probes or genes that provide reference points for physical mapping of 7p. Three reciprocal translocations with one of the breakpoints in 7p13 mark the location of a gene involved in Greig cephalopolysyndactyly syndrome. To define an area in which we could identify candidates for this developmental gene, we established a macrorestriction map using probes flanking the putative gene region. The Greig translocations were found to be located within a 630-kb NotI restriction fragment.
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